MATHEMATICS
JAMB 2011 - Question 21
Mathematics 2011 JAMB Past Questions - Question 21: Find the sum of the first 18 terms of the series 3,6,9,......36.
A:
B:
C:
D:
Correct Answer
B
Explanation
3,6,9,...,36a = 3 d = 3 I = 36, n = 18Ssubn = n/2 <2a+(n-1)dSsub18 = 18/2 <2x3+(18-1)3> = 9<6+(17x3) = 9<6+51> = 9 (57) = 513The given series is an arithmetic series with a common difference of 3. To find the sum of the first 18 terms, we can use the formula for the sum of an arithmetic series:Sn = (n/2)(2a + (n-1)d)Where Sn is the sum of the first n terms, a is the first term, and d is the common difference.In this case, n = 18, a = 3, and d = 3.Plugging in these values into the formula, we have:S18 = (18/2)(2(3) + (18-1)(3))Simplifying further:S18 = 9(6 + 17(3))S18 = 9(6 + 51)S18 = 9(57)S18 = 513Therefore, the sum of the first 18 terms of the series 3, 6, 9, ...... 36 is 513.
Frequently Asked Questions
Examkits is a JAMB CBT practice platform that provides over 20 years of past questions, Post UTME questions, and detailed video solutions to help students prepare for their exams.
You can practice JAMB past questions online, on Android, or on a desktop using the Examkits app. Just register on our website and choose your preferred device.
Yes. Our Android and Windows versions support offline usage. Once downloaded and activated, no internet is required to use most of the features.
Yes, Examkits provides detailed video explanations for all JAMB past questions from 2000 to 2024, helping students understand how to solve each problem.
Examkits offers free practice for some subjects. However, full access requires a one-time affordable activation fee for each version of the app.